• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >Luminescent Quadrupolar Borazine Oligomers: Synthesis, Photophysics, and Two-Photon Absorption Properties
【24h】

Luminescent Quadrupolar Borazine Oligomers: Synthesis, Photophysics, and Two-Photon Absorption Properties

机译：发光四极硼嗪低聚物：合成，光物理和双光子吸收特性。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A set of monodisperse bent donor-acceptor-donor-type conjugated borazine oligomers, BnNn+1 (n=1-4), incorporating electron-rich triarylamine donor and electron-deficient triarylborane acceptor units has been prepared through an iterative synthetic approach that takes advantage of highly selective silicon-boron and tin-boron exchange reactions. The effect of chain elongation on the electrochemical, one-and two-photon properties and excited-state photodynamics has been investigated. Strong intramolecular charge transfer (ICT) from the arylamine donors to boryl-centered acceptor sites results in emissions with high quantum yields (Phi(fl)>0.5) in the range of 400-500 nm. Solvatochromic effects lead to solvent shifts as large as similar to 70 nm for the shortest member (n=1) and gradually decrease with chain elongation. The oligomers exhibit strong two-photon absorption (2PA) in the visible spectral region with 2PA cross sections as large as 1410 GM (n=4), and broadband excited-state absorption (ESA) attributed to long-lived singlet-singlet and radical cation/anion absorption. The excited-state dynamics also show sensitivity to the solvent environment. Electrochemical observations and DFT calculations (B3LYP/6-31G*) reveal spatially separated HOMO and LUMO levels resulting in highly fluorescent oligomers with strong ICT character. The BnNn+1 oligomers have been used to demonstrate the detection of cyanide anions with association constants of log K > 7.
机译：已通过迭代合成方法制备了一组单分散弯曲的供体-受体-供体型共轭硼嗪低聚物，BnNn + 1（n = 1-4），其中结合了富电子的三芳基胺供体和缺电子的三芳基硼烷受体单元高度选择性的硅-硼和锡-硼交换反应的优势。研究了链伸长对电化学，一光子和二光子性质以及激发态光动力学的影响。从芳基胺供体到以硼基为中心的受体位点的强分子内电荷转移（ICT）导致了在400-500 nm范围内具有高量子产率（Phi（fl）> 0.5）的发射。溶剂变色效应导致最短成员（n = 1）的溶剂位移大至类似于70 nm，并随着链伸长而逐渐降低。这些低聚物在可见光谱区具有很强的双光子吸收（2PA），其2PA截面高达1410 GM（n = 4），宽带激发态吸收（ESA）归因于长寿单重态单峰和自由基阳离子/阴离子吸收。激发态动力学也显示出对溶剂环境的敏感性。电化学观察和DFT计算（B3LYP / 6-31G *）揭示了HOMO和LUMO在空间上分开的水平，从而导致了具有强ICT特性的高荧光低聚物。 BnNn + 1低聚物已用于证明检测缔合常数log K> 7的氰化物阴离子。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号